package cmds

import (
	"errors"
	"os"
	"strings"
)

func Eval(cmd string) error {
	args := strings.Split(cmd, " ")
	switch args[0] {
	case "cd":
		if err := chDir(args); err != nil {
			return err
		}
		break
	case "export":
		if err := export(args); err != nil {
			return err
		}
		break
	case "unset":
		if len(args) == 1 || len(args) >= 3 {
			return errors.New("usage: unset {name}")
		}
		os.Unsetenv(args[1])
		break
	case "set":
		if len(args) > 1 {
			set(args)
		} else {
			printenv()
		}
		break
	case "exit":
		if err := exit(args); err != nil {
			return err
		}
		break
	case ":":
		return nil
	}
	return nil
}